| We introduce the processes of rewriting reduction and pruning reduction on Munn trees (finite birooted trees with labelled edges) and use them to develop a general strategy to solve the idempotent word problem for inverse monoid presentations. The process of rewriting reduction on Munn trees is a generalization of the standard processes of rewriting on strings that is widely studied in computer science. The process of pruning reduction is a geometric adaptation of the process of rewriting reduction on Munn trees and is introduced as a natural way to deal with Munn trees, which may be viewed as two dimensional structures. The main part of the dissertation is devoted to a class of inverse monoid presentations of the form... |